Hydraulic press



Oct. 10, 1933. wlEDMANN 1,930,155 7 HYDRAULIC PRESS 2 Sheets-Sheet 1Filed April 6, 1951 Qwwntogc ERNST WEDMANN.

E. WlEDMANN HYDRAULIC PRESS Oct. 10, 1933.

Filed April 6, 1951 2 Sheets-Sheet 2 Hw 9w wv WV \N Wm VM 3 hm v \T kmNY OH W mm mm INT RrVI/Z 2v I ll! Vm gwwnto'o ERNST WEDMANN.

Patented; Oct. 10,

. erated by the press is provided with arranged in a main cylinder,motor for reciproc Ernst Wiedma nn, Milwaukee, with The Oilgear Company,poration of Wisconsin 5 1,930,155 res AT-Eur orl-rcsmasonic mess.

Application April 6:

16 Claim!- This invention relates to hydraulic presses.

The press to ticular has a ram and airam m at highspeed, a reserto theram cylinder and V for receiving liquidtherefrom during the highmotor'for moving the re 5 voir for supplying liquid which the inventionapplies in'parcylinder, a hydraulic speed movement of the ram, a valvecontrolling the flow of liquid to-and and an intensifying ram from theram cylinder,

for exerting pressure upon the liquid inthe ram cylinder after the ramhas engaged 'the work.

The invention has as an object to 'providea high speed heavy duty'presswhich may be opa pump of relatively smallcapacity.

Another'object is to provide apress of this character which is highlyefilcient.

According to the invention in one of its aspects,

for supplying liquid fr ating the a main ram which is a separatehydraulic main ram. into and the work,'a reservoir eely to the maincylinder and receiving liquid therefrom during'reeiprocation of the mainram ing ram for advancing exert pressure upon by'the motor, anintensifyinto the main cylinder to the liquid therein and to closecommunication between the main cylinder and the reservoir, and means forcausing fying ram to advance into the'main cylinder after the main ramThe invention has stalled against theworlr.v

invention in another aspect,

from the high speed motor is cting the intensifying ram.

is exemplified by the press shown in the acompanying drawings in whichthe views are as follows:

Fig. l is a front tion, of a high spee tion is embodied.

Fig. 2 is a schem circuit.

Fig. 3 is a longitudinal trol valve.

This press has elevation, partly in central secd press'in which theinven-.

atic drawing of the hydraulic section through a con a base I forsupporting a lower block 3 connected to the base 1 elation thereto byfour shouldered bolts 4, and a reservoir 5 arranged upon the top of thecylinder block 3.

The cylinder block 3 has a ram cylinder 6 the vertical centerline of thelinder '7 formed therein upon each side of the ram cylinder 6 andparallel thereto.

The ram cylinder and provided upon its 9 for supporting an upper 6 has aram 8 fitted therein lower end with a die block die 10.

Each of the auxiliary cylinders '7 has a piston and connected by its rod12 to 11 fitted therein the die,block 9 for raising 8 at high speed.

and lowering the ram the intensi-.

- tail nor described herein.

,assignor to no. 52am gel. 138-17) The ram cylinder 6 bass bore 13formed inits upper head in alinement with a bore 14 which.

extends through the bottom of the reservoir 5 k and through the lowerhead of ram cylinder 15- which is arranged within the reservoir 5 andshown as being formed integral therewith. v

The bore 14 is intersected intermediate its ends provide communicationbetween the reservoir 5 and the ram cylinder 6. 1

;The bore 14has an intensifying ram 17 fitted therein and provided atits upper end witha piston 18 which is fitted in the cylinder 15.

When the intensifying ram 1'7. is lowered, it firstinterruptscommunication between the reservoir '5 and the ram cylinder 6by ner ends of the passageways 16 and then it exerts pressure upon theliquid in thecylinder 6.to thereby cause the ram 8 to.exert a highpressure upon a piece of work arranged between the dies 2 and 10.

Thepress is operated by liquid supplied by a shownin the drawings asbeing flow type, such as the pump pump '19 which is of the reversibleshown in Patent As this pumpis well-known and in extensive commercialuse, it has not been illustrated in de- The ram 8 and the pistons 11 areraised at high speed by liquid delivered to the lower ends of thecylinders! through a pipe 21, a check valve 22, and a pipe 23 whichisconnected to one side of the pump 19. v

The check valve 22 has a low pressure resistansintensifying closing thein- The ram 1'! thus functions as avalve to control No. 1,798,198 issuedMarch 31'. j 1931 toJohn P, Ferris.

ance valve 24 connected in parallel therewith which resists the flow ofliquid from the cylinders 7 to the pump 19 and has sufficient resistanceto hold the ram 8 against downward movement when the press is idle.

The 8 and the pistons 11 are lowered at high speed by liquid deliveredto the upper ends of the cylinders 7 through a pipe 25, a check'valve 26which has a. low pressure resistance valve 2'7 connected in paralleltherewith, and a pipe 28. which is connectedto the other side of thepump The pipe 25 is connected intermediate its ends by a'pipe 29 to aport 30 in which has .a hydraulically operated plunger 31 to control theflow of liquid therethrough.

One stem or the plunger 31 is fitted in a cylinder 32, which is arrangedat one end of the valve the control valve 20 20 and connected to thepipe 21, and the other stem of the plunger 31 is fitted in a cylinder 33which is arranged at the other end of the valve 20 and connected to thepipe 29 by a pipe 34 having a check valve 35 and a high pressureresistance valve 36 connected in parallel therein.

The port 30 is normally open to a port 37 which is connected by a pipe38 to the lower end of the cylinder 15 for delivering liquid thereto toraise the intensifying ram 17.

The lower end of the cylinder 15 is also preferably open to thereservoir 5 through a check valve 39 which allows liquid to flow freelyfrom the reservoir 5 into the cylinder 15 when the ram 17 is beingraised but prevents the escape of liquid from the cylinder 15 into thereservoir 5. The

check valve 39 may be connected to the pipe 38,

as shown.

When the ram 17 rises, liquid is discharged from the upper part of thecylinder 15 into the reservoir 5 through a pipe 40, which connects theupper end of'the cylinder 15 to a port 41 formed in the valve 20, andthrough a pipe 42 which connects the reservoir 5 to the valve 20 at bothends of its valve chamber.

The level of the liquid in the reservoir 5 is limited by an overflowpipe 43 which has one end connected thereto near the upper end thereofand its other end connected to the sump of the pump 19. When the pressis idle, the control lever 44 of the pump 19 is in its neutral positionas shown in Fig. 2, the ram 8 is supported by the liquid held in thelower ends of the cylinders 7 by the low pressure resistance valve 24,and the ram 17 is supported by liquid held in the lower end of thecylinder 15 by the low pressure resistance valve 27.

,To start the press, the operator moves the control lever 44 to ortoward the full speed downward position 45 indicated in dotted lines,and the pump 19 delivers liquid through the pipe 28, the check valve 26and the pipe 25 to the upper ends of the cylinders 7 and moves thepistons 11 and the ram 8 downward at high speed, and pres sure extendsfrom the 29, the valve 20 and the pipe 38 to the lower end of thecylinder 15 and holds the ram 17 in its upper position.

A's the ram 8 and pistons 11 move downwardly, liquid flows from therservoir 5 through the passageways 16 and bores 13 and 14 into the upperend of the cylinder 6, and liquid is exhausted from the lower ends ofthe cylinders 7 through the pipe 21, the resistance valve 24 and thepipe 23 to the intake of the pump 19.

When the ram 8 stalls, the pressure in' the pipes 25 and 29 rises andliquid breaks through the high pressure resistance valve 36, enters thecylinder 33, and moves the plunger 31 to the right into the positionshown in Fig. 3.

Moving the plunger 31 to the right closes the port 37 to the port 30 andopens the port 41 to the port 30 to allow pressure liquid to flowthrough the pipe 40 to the top of the cylinder 15 and force the ram 17downward and to allow the liquid in the lower part of the cylinder 15 toexhaust through the pipe 38, the valve 20 and the pipe 42 into thereservoir 5, the excess liquid delivered to the reservoir 5 escapingthrough the overflow pipe 43 to the sump of the pump 19.

When the ram 17 moves downward, it first closes the passageway 16,thereby preventing the liquid in the cylinder 6 from escaping, and thenit exerts pressure upon the liquid in the cylinder 6 and causes the ram8 to exert a high pressure pipe 25 through the pipe in dotted lines andliquid is delivered by the pump 19 through the pipe 23, the check valve22 and the pipe 21 to the lower ends of the cylinders 7 and raises thepistons 11 and the ram 8, and liquid enters the cylinder 32 on the valve20 and moves the plunger 31 to its initial position.

As the pistons 11 rise, liquid is expelled from the upper ends of thecylinders 7 into the pipe 25 but the return of this liquid to the pump19 is resisted by the valve 27, and the liquid flows through the pipes25 and 29, the valve 20 and the pipe 38 to the lower end of the cylinder15 and raises the ram 17.

However, a greater amount of liquid must be expelled from the upper endof the cylinder 6 than from the upper ends of the cylinders 7 and thisliquid raises the ram 17 until the passageways 16 are partly open.

During this part of the movement of the ram 17, it moves at a higherspeed than would be produced by the liquid expelled from the cylinders7, and liquid is drawn into the cylinder 15 through the check valve 39.

The ram 8 then expels liquid from the cylinder 6 through the bores 13and 14 and the passageways 16 into the reservoir 5 and the liquidexpelled from the cylinders 7 raises the ram 17 until it stalls at thetop of its stroke and then liquid breaks through the low pressureresistance valve 27 and flows through the pipe 28 to the intake of thepump 19.

The liquid expelled from the upper end of the cylinder 15 flows throughthe pipe 40, the valve 20 and the pipe 42 to the reservoir 5.

When the ram 8 has been raised the desired distance or reaches the topof its stroke, the operator returns the lever 44 to its initial orneutral position and the output of the pump 19 falls to zero.

The invention herein set forth is susceptible of various modificationswithout departing from the scope thereof as hereafter claimed.

The invention is hereby claimed as follows:

1. A hydraulic press, comprising a stationary die block, a main cylinderspaced from said die block, a main ram arranged in said cylinder, aseparate double-acting hydraulic motor connected to said ram forreciprocating it toward and from said die block, a reservoir containingliquid and having a passageway communicating with said main cylinder forallowing liquid to flow therebetween, an auxiliary cylinder having abore communicating with said main cylinder, an intensifying ram arrangedin said auxiliary cylinder and said bore and extendable into said maincylinder and controlling the flow of liquid through said passageway,means for delivering pressure liquid to said motor to operate the sameand cause reciprocation of for delivering pressure cylinder to operatesaid 2. A hydraulic press, comprising a stationary die block, a main cyder spaced from said die block, a main ram arranged in said cylinder, ahydraulic motor connected to said ram for reciprocating it toward andfrom said die block, a reservoir containing liquid and having apassageway communicating with said main cylinder for allowing liquid toflow therebetween, an auxiliary cylinder arranged within said reservoirand having a bore communicating with said main cylinsaid main ram, andmeans liquid to said auxiliary intensifying ram.

' inder and controlling the der, an intensifying ram arranged in saidauxiliary cylinder and said bore and extendable into said main cylinderand controlling the flow of liquid through said passageway, means fordelivering pressure liquid to said motor to operate the same and causereciprocation of said main ra n, and means for deliveringpressure-liquid to said auxiliary cylinder to operate said intensifyingram.

3. A hydraulic press, comprising a stationarydie block, a main cylinderarranged above said die block, a main ram arranged in said cylinder, aseparate double-acting hydraulic motor connected to said ram forreciprocating it toward and from said die block, a reservoir forcontaining liquid carried by said main cylinder upon the upper endthereof and having a passageway communicating therewith for allowingliquid to flow therebetween, an auxiliary cylinder having a borecommunicating with said maincylinder, an intensifying ram arranged insaid auxiliary cylinder and said bore and extendable into said maincylfiow of liquid through said passageway, means for delivering pressureliquid to said motor to operate the same and cause reciprocation of saidmain ram, and means for delivering pressure liquid to said auxiliarycylinder to operate said intensifying ram.

4. A hydraulic press, comprising a stationary die block, a main cylinderarranged above said die block, a main ram arranged in said cylinder, ahydraulic motor connected to said ram for reciprocating it toward andfrom said die block, a reservoir for containing liquid carried by saidmain cylinder upon the upper end thereof and having a passagewaycommunicating therewith for allowing liquid to flow therebetween, anauxiliary cylinder arranged within said reservoir and having a borecommunicating with said main cylinder, an intensifying ram arranged insaid auxiliary cylinder and said bore and extendable-into said maincylinder and controlling the flow of liquid through said passageway,means for delivering pressure liquid to said motor to operate the. sameand cause reciprocation of said main ram, and means for deliveringpressure liquid to said auxiliary cylinder to operate said intensifyingram.

5. A hydraulic press, comprising a stationary die block, a main cylinderspaced from said die block, a main ram arranged in said cylinder, ahydraulic motor connected to said ram for reciproeating it toward andfrom said die block, a reservoir containing liquid and having apassageway communicating with said main cylinder for allowing liquid toflow therebetween, an auxiliary cylinder arranged within said reservoirand having a bore communicating with said main cylinder, an intensifyingram arranged in said auxiliary cylinder and said bore and extendableinto said main cylinder and controlling the flow of liquid through saidpassageway, and means for delivering pressure liquid to said press tooperate the same including a valve' for first directing said liquid tosaid motor to advance said main ram at high speed and automaticallyoperable to divert the delivery of said liquid to said auxiliarycylinder to advance said intensifying ram.

6. A hydraulic press, comprising a stationary die block, a main cylinderarranged above said die block, a main ram arranged in said cylinder, aseparate double-acting hydraulic motor connected to said rain forreciprocating it toward and from said die block, a reservoir forcontaining liquid carried by said main cylinder upon the passageway,

at high speed and hydraulically operable to upper end thereof and havinga passageway communicating therewith for allowing liquid to flowtherebetween, an auxiliary cylinder having a bore communicating withsaid main cylinder, an intensifying ramarranged in said auxiliarycylinder and said bore and extendable into said main cylinder andcontrolling the flow of liquid through said passageway, and means fordelivering pressure liquid to said press to operate the same including avalve for first directing said liquid to said motor to advance said mainram at high speed and automatically operable tov divert the delivery ofsaid liquid to said aux'liary cylinder to advance said intensifying ram.

'7. A hydraulic press, comprising a stationary die block, a maincylinder arranged above .said

die block, a main ram arranged in said cylinder,

a hydraulic motor connected to said ram for reciprocating it toward andfrom said die block, a reservoir for containing liquid carried by saidmain cylinder upon the upper end thereof and having a passagewaycommunicating therewith for allowing liquid to flow therebetween,.anauxiliary cylinder arranged within said reservoir and having a borecommunicating with said main cylinder, an intensifying ram arranged insaid auxiliary cylinder and said bore and extendableinto said maincylindenand controlling the flow of liquid through said passageway, andmeans for delivering pressure liquid to said press to operate the sameincluding a valve for first direct? ing said liquid to said motor toadvance said main ram at high speed and automatically operable todivertthe delivery of said liquid to said auxiliary cylinder to advancesaid intensifying ram.

8. A hydraulic press, comprising a stationary die block, a main cylinderspaced from said die block, a main ram arranged in said cylinder,aseparate double-acting hydraulic motor connected to said ram forreciprocating it toward and from said die block, a reservoir containingliquid and having a passageway communicating with said main cylinder forallowing liquid to flow therebetween, an auxiliary cylinder having abore communicating with said main cylinder, an intensifying ram arrangedin said auxiliary cylinder and said bore and extendable into said maincylinder and controlling the flow of liquid through said and means fordelivering pressure liquid to said press to operate the same including avalve hydraulically operable in response to the pressure of said liquidreaching a predetermined maximum for directing said liquid first to saidmotor to advance said main ram at high speed and then to said auxiliarycylinder to advance said intensifying ram.

9. A hydraulic press, comprising a stationary die block, a main cylinderspaced from said die block, a main ram arranged in said cylinder, ahydraulic motor connected to said ram for reciprocating it toward andfrom said die block, a reservoir for oontainingliquid arranged abovesaid main cylinder and having a passageway cornmunicating therewith forallowing liquid to flow therebetween, an auxiliary cylinder arrangedwithin said reservoir and having a bore communicating with said maincylinder, an intensifying ram arranged in saidauxiliary cylinder andsaid bore and extendable into said main cylinder and controlling thefiow of liquid through said passageway, and means for deliveringpressure liquid to said press to operate the same including a valve forfirst directing'said liquid to said motor to advance said main ram vertthe delivery of said liquid to said auxiliary cylinder to advance saidintensifying ram upon the pressure of said liquid reaching apredetermined maximum.

10. A hydraulic press, comprising a stationary die block, a maincylinder arranged above said die block, a main ram arranged in saidcylinder, a separate double-acting hydraulic motor connected to said ramfor reciprocating it toward and from said die block, a reservoir forcontaining liquid carried by said main cylinder upon the upper endthereof and having a passageway communicating therewith for allowingliquid to flow therebetween, an auxiliary cylinder having a borecommunicating with said main cylinder, an intensifying ram arranged insaid auxiliary cylinder and said bore and extendable into said maincylinder and controlling the flow of liquid through said passageway, andmeans for delivering pressure liquid to said press to operate the sameincluding a valve hydraulically operable in response to the pressure ofsaid liquid reaching a predetermined maximum for directing said liquidfirst to said motor to advance said main-ram at high speed and then tosaid auxiliary cylinder to advance said intensifying ram.

11. A hydraulic press, comprising a stationary die block, a maincylinder arranged above said die block, a main ram arranged in saidcylinder, a hydraulic motor connected to said ram for reciprocating ittoward and from said die block, a reservoir for containing liquidcarried by said main cylinder upon the upper end thereof and having apassageway communicating therewith for allowing liquid to flowtherebetween, an auxiliary cylinder arranged within said reservoir andhaving a bore communicating with said main cylinder, an intensifying ramarranged in said auxiliary cylinder and said bore and extendable intosaid main cylinder and controlling the flow of liquid through saidpassageway, and means for delivering pressure liquid to said press tooperate the same including a valve for first directing said liquid tosaid motor to advance said main ram at high speed and hydraulicallyoperable to divert the delivery of said liquid to said auxiliarycylinder to advance said intensifying ram upon the pressure of saidliquid reaching a predetermined maximum.

12. In a hydraulic press, the combination of a main cylinder, a main ramarranged in said cylinder, a hydraulic motor mechanically connected tosaid ram for reciprocating it, means for delivering pressure liquid tosaid motor to operate the same, a reservoir arranged above said maincylinder for supplying liquid thereto and receiving liquid therefromduring reciprocation of said ram, an auxiliary cylinder arranged withinsaid reservoir and having a bore communicating with said main cylinderand a passageway for connecting said bore to said reservoir, anintensifying ram arranged in said auxiliary cylinder and extendablethrough said bore to close said passageway and to exert pressure uponliquid within said main cylinder, and

means for delivering liquid to each end of said auxiliary cylinder toreciprocate said intensify-- ing ram.

13. In a hydraulic press, the combination of a main vertical cylinder, amain ram arranged in said cylinder, a hydraulic motor mechanicallyconnected to said rain for reciprocating it, means for deliveringpressure liquid to said motor to operate the same, a reservoir supportedupon said main cylinder for supplying liquid thereto and receivingliquid therefrom during reciproca- E tion of said ram, an auxiliarycylinder arranged within said reservoir and having bore communicatingwith said main cylinder and a passageway for connecting said bore tosaid reservoir, an intensifying ram arranged in said 8 auxiliarycylinder and extendable through said bore to close said passageway andto exert pressure upon liquid within said main cylinder, and means fordelivering liquid to each end of said auxiliary cylinder to reciprocatesaid intensify- 91 ing ram.

14. In a hydraulic press, the combination of a main cylinder, a main ramarranged in said cylinder, a hydraulic motor mechanically connected tosaid ram for reciprocating it, means for delivering pressure liquid tosaid motor to operate the same, a reservoir arranged above said maincylinder for supplying liquid thereto and receiving liquid therefromduring reciprocation of said ram, an auxiliary cylinder arranged withinsaid reservoir and having a bore communicating with said main cylinderand a passageway for connecting said bore to said reservoir, anintensifying ram arranged in said cylinder and extendable through saidbore to close said passageway and to exert pressure upon liquid withinsaid main cylinder, means for delivering liquid to each end of saidauxiliary cylinder to reciprocate said intensifying ram, and meansincluding a check valve for allowing liquid to flow from said reservoirinto said auxiliary cylin-' der but preventing said liquid from flowingin the opposite direction.

15. In a hydraulic press, the combination of a ramcylinder, a ramarranged in said cylinder, a hydraulic motor connected to said ram foradvancing and retracing the same, an auxiliary cylinder, a plungerarranged in said auxiliary cylinder and extendable into said ramcylinder, means 'for delivering liquid to said motor to advance andretract said ram, means for delivering liquid to one end of saidauxiliary cylinder to advance said plunger into said ram cylinder, andmeans for directing exhaust liquid from said motor to the other end ofsaid auxiliary cylinder to retract said plunger.

16. In a hydraulic press, the combination of a ram cylinder, a ramarranged in said cylinder, a hydraulic motor connected to said ram foradvancing and retracting the same, an auxiliary 131 cylinder, a plungerarranged in said auxiliary cylinder and extendable into said ramcylinder, means for delivering liquid to one end of said motor toadvance said ram until it meets a predetermined resistance and therebycauses an 35 increase in the pressure of said liquid, means responsiveto said increase in pressure to divert said delivery of liquid to oneend of said auxiliary cylinder to advance said plunger into said ramcylinder to thereby increase the force exerted by said ram, means forthen delivering liquid to the other end of said motor to retract saidram, and means for directing exhaust liquid from

